I was wondering, do you unlock all the characters in adventure mode? Because if you do, they made it too easy to unlock the hidden characters. I'm asking this to decide if I want to continue the adventure mode or if I want to wait until I unlock them all beforehand.

There are 2 ways to unlock all characters. you can do all of SSE and then go back to get the three side quest characters or you can just do vs. matches. 450 vs matches unlocks everyone. and to get your friend code you have to log on to the wifi and go to friend roster. your code should be at the top there.

I'm not so sure if this is true. I beat SSE (now have about 82% completion rate) and didn't get Wolf or Toon Link from SSE (only two I can remember not getting and haven't got Wolf yet just assume from the leaks). If you do get a character from having a higher completion rating I would imagine it would only be at 100% and only one more character. It would be odd to get someone for 90% completion and can't think of any other things SSE is hiding from me.

Yah go through the swamp, past the moving part. Then go to the area where there are the flat launchers and the barrel cannons. after you defeat all the hammer bros and parakoopas on that one platform, swim to the next platform. There should be door. Go inside and you'll see jigglypuff in the stadium in the first level. Shes kind of difficult so bring one of your better players. Also it is like a regular 1-stock match you dont get to switch players once it starts and if you lose you have to go through the swamp all over again.